Typically, search engines order search results prior to presenting the search results to a user. The order usually takes the form of a “relevance ranking”, where the matching item with the highest relevance ranking is the item considered most likely to satisfy the interest reflected in the search criteria specified by the user.
The specific techniques for determining relevance ranking vary from implementation to implementation. One factor used by many ranking mechanisms to determine relevance is the “quality” of a web page. When all other factors are equal, pages that are “popular” are given higher rankings than pages that are visited less frequently.
Ranking mechanisms may determine the quality of web pages based on information collected by the search engine. For example, one type of information that can be collected by the search engine is how users use the search engine. Thus, if users of the search engine frequently select a particular link from the search results, then the quality weight of the corresponding page may go up, therefore giving the page a higher relevance ranking.
Ranking mechanisms may also determine quality of web pages based on hyperlink relationships between web pages. One technique that uses hyperlink relationships to establish a measure of quality is known as the PageRank technique.